Substituted tropic acid n-fr-picolyl



United States Patent 1 2,726,245 SUBSTITUTED TROPIC ACID N-('y-PICOLYL)- AMIDES AND PROCESS FOR THE MANU- FACTURE THEREOF Grald Rey-Bellet and Hans Spiegelberg, Basel, Switzerland, assignors to Holfmann-La Roche Inc., Nutley, N. J., a corporation of New Jersey No Drawing. Application September 24, 1953,

Serial No. 382,213

Substituted tropic acid amides, more particularly those of the following formula onion R tH Co N wherein R stands for a methyl, ethyl or allyl radical, have been found to be valuable drugs. Thus, the said compounds possess excellent spasmolytic properties and are of low toxicity for humans and animals. These drugs show a marked antiacetylcholine action, especially in Kiihls blood pressure test on cats.

The above mentioned novel compounds may be prepared according to the present invention by condensation of tropic acid chloride with methyl-, ethyl-, or allyl-( picolylJ-amine or by condensation of acetyl-tropic acid chloride with ethyl-, methylor allyl-(' -picolyD-amine and subsequently splitting off the acetyl group. The said novel compounds may be reacted with acids to form acid addition salts, such as for example the hydrochloride, the hydrobromide, the sulfate.

The substituted 'y-picolyl-amines, used as starting material, may be obtained for example by reacting a 4-halogeno-methyl-pyridine with methyl, ethyl or allylatnine or by reacting N-(p-toluene-sulphonyl)-4aminomethyl-pyridine with a methyl, ethyl or allyl halide or with the corresponding sulfate and subsequent deacylation.

Example 1 parts by weight of -chloromethylpyridine-hydrochloride in 60 parts of water is added dropwise to 250 parts by weight of a 50% aqueous methylamine solution, the temperature being maintained between l0 and -5 C. Stirring is continued for two hours at 20-25 C. and for one hour at 60 C., whereupon the mixture is cooled down and saturated in the cold with solid potassium hydroxide. The mixture is extracted with ether and, after having distilled off the ether, the residue is distilled; the methyl-('y-picolyD-amine, a water-like liquid, boils at 95-96 C. under a pressure of 13 mm. Hg; its dihydrochloride melts at 231-233 C.

To a mixture of 34.3 parts by weight of methyl-(vpicolyl)-amine and 28 parts by weight of dry pyridine in 225 parts by weight of dry chloroform, acetyl-tropic acid chloride prepared from 45 parts by weight of tropic acid are slowly added, while stirring and cooling with ice Water. To complete the reaction, the mixture is then stirred for an additional hour at 25 C. The chloroform solution is then diluted with 200 parts by weight of ether and agitated with 3 N hydrochloric acid. The weakly Congo acid solution is heated for 1 hour in the steam bath, the acetyl group of the reaction product being thereby split off. The mixture is filtered over charcoal and concentrated ammonia is added in excess. The condensation product precipitated is taken up in chloroform, whereupon the chloroform solution is dried and concentrated. The residue is recrystallized in a mixture of ethyl acetate and low boiling petro- A solution of 82 2,726,245 r mmed Dec. s, 1955 Example 2 A solution of 82 parts by weight of 'y-chloromethylpyridine hydrochloride in 60 parts of water is added dropwise, at ()5 C., to 250 parts by weight of a 50% aqueous ethyl amine solution. The mixture is stirred for .1 hour at 60 C., whereupon it is cooled down and separated in the cold with solid potassium hydroxide. The oil-formed is separated ofl, dried over potassium hydroxide and distilled. The ethyl-('y-picolyD-amine formed boils over at lO3-104 C. under a pressure of 13 mm. Hg. Its dihydrochloride melts at 198-200 C.

To a mixture of 48.7 parts by weight of ethyl-('y-picolyl)-amine and 36 parts by weight of dry pyridine in 220 parts by weight of dry chloroformis slowly added, while stirring and cooling with ice Water, crude acetyltropic acid chloride, prepared from 60 parts by weight of tropic acid. To complete the reaction, the mixture is stirred for one additional hour at 23 C. Thereupon the chloroform solution is diluted with 200 parts by weight of ether and agitated with 3 N hydrochloric acid. The weakly Congo acid solution is heated for 1 hour in a steam bath, the acetyl group of the reaction product being thereby split oif, and the mixture is filtered over charcoal. Upon adding concentrated ammonia in excess, the condensation product separates and is taken up in chloroform. The chloroform solution is dried and distilled, the tropic acid N-ethyl-N- -picolyl)-amide being thereby obtained in the form of a thick oil, which crystallizes after prolonged time and which then melts at 96 97 C.

Example 3 parts by weight of 'y-chloromethylpyridine-hydrochloride in 60 parts of Water is added dropwise to 175 parts by weight of pure allyl amine. The temperature is maintained below 10 C. by means of an ice water bath. The mixture is then stirred for 2 hours at 25 C. and for 1 hour at 50 C., it is cooled down and saturated in the cold with solid potassium hydroxide. The oily layer formed is separated, dried with solid potassium hydroxide and distilled, the ally -('y-picolyl)-amine formed boiling over at 120-121 C. under a pressure of 13 mm. Hg; the dihydrochloride thereof melts at 184-185 C.

To a mixture of 50 parts by weight of allyl-(' -picolyD- amine and 30.5 parts by weight of dry pyridine in 200 parts by weight of dry chloroform, crude acetyl-tropic acid chloride, prepared from 57.5 parts by Weight of tropic acid, is slowly added while stirring and cooling with ice water. The reaction is completed by stirring for additional minutes at 25 C. Thereupon, the chloroform solution is diluted with 200 parts by weight of ether and agitated with 3 N hydrochloric acid. The weakly Congo acid solution is heated for 1 hour in a steam bath to split off the acetyl group of the reaction product, the mixture is filtered over charcoal and concentrated ammonia is added in excess. The condensation product formed is extracted with chloroform, the chloroform extract is dried and concentrated. The tropic acid N-allyl- -(y-picolyl)-amide is a thick oil, the hydrochloride of which melts at 64-66 C.

Example 4 To a mixture of 27.2 parts by weight of ethyl-('y-picolyl)-amine (Example 2) and 21 parts by weight of triethyl amine in 300 parts by weight of dry chloroform is added dropwise, while stirring, crude tropic acid chloride prepared from 33.2 parts by weight of tropic acid. The temperature is thereby maintained below 20 C. by cooling with an ice water bath. Once the reaction is complete, the chloroform solution is washed with water, diluted A solution of 82 with 200 parts by weight of ether and agitated with 3 N amine and treating the condensation product formed with hydrochloric acid. The hydrochloric acid solution is filan acid to form tropic acid N-methyl-(-y-picolyD-amide. tered over charcoal and, in the cold, concentrated am 3. A process according to claim 1, which comprises remonia is added in excess, the tropic acid N-ethYI-N-(7- acting acetyl-tropic acid chloride with ethyl-('y-picolyD- picolyl)-amide precipitating thereby. The latter is taken 5 amine and treating the condensation product formed with up in chloroform, the chloroform solution is dried over an acid to form tropic acid N-ethyl-(v-picolyl)-amide. sodium sulphate and the chloroform is distilled off. The 4. A process according to claim 1, which comprises residue is recrystallized in a mixture of ethyl acetate and reacting acetyl-tropic acid chloride with allyl-(y-picopetroleum ether to yield colorless crystals of tropic acid lyl)-amine and treating the condensation product formed N-ethyl-N-(' -picolylyamide of melting point 9697 C. 10 with an acid to form tropic acid N-allyl-(v-picolyh- The hydrobromide melts at 147-149 C., the hydrochloamide. ride at 123-125 C. 5. A compound selected from the group consisting of We claim: tropic acid N-methyl-N-( y-picolyl)-amide, tropic acid 1. A process for the manufacture of substituted tropic N-ethyl-N-('y-picolyD-arnide, tropic acid N-allyl-N-(yacid N-(y-picolyl) -amidesand acid addition salts thereof 15 picolyl)-amide and the acid addition salts thereof. which comprises reacting acetyl tropic acid chloride, with a member of the group consisting of methyl-(y-pico- References Cited in the file Of this Patent YU- fl y (v-P -(v-p n- UNITED STATES PATENTS amine an y r0 yzingo t eacety group. 2. A process according to claim 1, which comprises re- 20 gi fggfizi ga Z acting acetyl tropic acid chloride with methyl-('y-picolyD- y y 

5. A COMPOUND SELECTED FROM THE GROUP CONSISTING OF TROPIC ACID N-METHYL-N-(R-PICOLYL)-AMIDE, TROPIC ACID N-ETHYL-N-(R-PICOLYL)-AMIDE, TROPIC ACID N-ALLYL-N-(RPICOL)-AMIDE AND THE ACID ADDITON SALTS THEREOF. 